Anna Lee

New membrane technologies based on novel organic, inorganic, and hybrid materials and with unprecedented functionality are reviewed.

Harvesting water from humid air via dewing can provide a viable solution to a water shortage problem where liquid-phase water is not available. Here we experimentally quantify the effects of wettability and geometry of the condensation substrate on the water harvest efficiency. Uniformly hydrophilic surfaces are found to exhibit higher rates of water condensation and collection than surfaces with lower wettability. This is in contrast to a fog basking method where the most efficient surface cons

Abstract Due to their exceptional high energy density, lithium-ion batteries are of central importance in many modern electrical devices. A serious limitation, however, is the slow charging rate used to obtain the full capacity. Thus far, there have been no ways to increase the charging rate without losses in energy density and electrochemical performance. Here we show that the charging rate of a cathode can be dramatically increased via interaction with white light. We find that a direct exposu

Abstract Numerous approaches are explored to achieve precise position registry of microparticles (MPs) with minimal defects; however, MP assembly in a periodic pattern or an arbitrary manner has been a challenging issue over the past several decades. Utilizing the position‐registered conductive MPs, polymer composites of the MPs are used as anisotropic conductive film (ACF) and soft interfacing. One of the remaining challenges is maintaining the MP positions while producing or utilizing the ACF.

Slippage of liquid over rough superhydrophobic surfaces that induce the Cassie-Baxter state decreases frictional force on the flow. This may easily lead to a hasty conclusion that liquid slip enhances the flow rate in rough channels. Here, we show that flow rates can be rather reduced by roughening and hydrophobizing microchannel walls to support liquid slippage, depending on the topography of the roughness. We consider theoretical models that predict liquid flow rates in channels of different r

We propose and investigate a minimal mechanism that makes use of differential swelling to modify the critical buckling conditions of elastic bilayer shells, as measured by the knockdown factor. Our shells contain an engineered defect at the north pole and are made of two layers of different crosslinked polymers that exchange free molecular chains. Depending on the size of the defect and the extent of swelling, we can observe either a decreasing or increasing knockdown factor. FEM simulations are

In artificial tactile sensing, to emulate the human sense of touch, independent perception of shear force and pressure is important. Decoupling the pressure and shear force is a challenging task for ensuring stable grasping manipulation for both soft and brittle objects. This study introduces a deformable ion gel-based tactile sensor that is capable of distinguishing pressure from shear force when pressurized shear force is applied in any direction. Recognition of the decoupled forces and precis

We report the design of an all-optical modulator based on the ultrafast nonlinear optical response of indium tin oxide (ITO) combined with the sharp spectral features of a high-Q resonant grating structure. Under optical excitation, a thin layer of ITO exhibits an ultrafast, reversible, and large intensity-dependent change in its refractive index. The grating structure provides rapid variation of the transmission coefficient, which is tuned to the epsilon-near-zero spectral region of ITO. The pr